The preparation of amine oxide surfactants by the oxidation of tertiary amines is of considerable commercial interest. Such surfactants are widely used in commercial cleaning compositions, especially high sudsing dishwashing detergents. However, it has now been discovered that some sources of amine oxide surfactants may be contaminated with residual amounts of nitrite materials, especially inorganic nitrites. Contamination by such nitrites may be tolerable under many circumstances. For some uses, however, the presence of nitrites may be undesirable, since they prospectively can react with other ingredients which may be present in fully formulated detergent compositions.
Detergent formulators presumably could arrange for special care to be taken during the manufacture of amine oxides in order to minimize the formation of undesirable nitrite contaminants. However, the manufacturer [formulator] of high volume, low-cost chemicals such as home-use detergents can ill-afford surfactants and other raw materials requiring special reaction techniques or special reactants, due to their expense.
The present invention solves the problem of contamination of amine oxide surfactants by nitrite materials using simple, cost-effective techniques. The invention herein thus affords access to a high quality supply of this class of surfactants.